Antioxidant radioprotective polyphenols derived from extracts

4.2 ANTIOXIDANT RADIOPROTECTIVE POLYPHENOLS DERIVED FROM PLANT EXTRACTS GIULIA DE ANGELIS1, ALESSIO VALLETTA1, VALENTINA PASQUALETTI3, NADIA MULINACCI2, ALESSANDRA MAMELI3, CAMILLA GIULIANI2, VITTORIA LOCATO3, LAURA DE GARA3, MARZIA INNOCENTI2, GABRIELLA PASQUA1. 1Department of Environmental Biology, “Sapienza” University of Rome, Piazz.le Aldo Moro 5, 00185 Roma, Italy; 2Department of Neurofarba, University of Florence, Via U. Schiff 6, 50019 Sesto Fiorentino - Florence, Italy; 3Laboratory of Plant Biochemistry and Food Science, University Campus Bio-Medico of Rome, Via Alvaro del Portillo 21 Rome, Italy During long-term space missions, astronauts are exposed to a variety of potentially harmful factors, including chemical contaminants and cosmic radiation (i.e. X-rays and γ-rays). Epidemiological studies have shown that exposure to medium-high doses of ionizing radiation increases the risk to develop several types of cancer, such as leukemia, brain tumor, thyroid, colon and lung (1). The exposure to ionizing radiation, are often associated with an overproduction of free radicals , mainly ROS (Reactive Oxygen Species) and RNS (Reactive Nitrogen Species), that the endogenous antioxidative systems fail to neutralize. The interaction of these agents with cells showed to cause alterations in the gene expression pattern, mutations, weakening of repair mechanisms inflammation to the gut mucosa premature aging, cancer, atherosclerosis, hypertension, Parkinson's disease, Alzheimer's disease, diabetes mellitus, colitis and rheumatoid arthritis (2). Currently, the use of chemical radioprotectors clinically tested i.e. thiols, aminothiols, thiadiazoles, benzothiazoles, is limited by their toxicity and their harmful health effects. For this reason, great attention is paid to the search for radioprotective compounds derived from plants. In this study the antioxidant properties of different natural plant extracts have been evaluated. For the preparation of the formulations have been used a pool of bioactive molecules most widely studied by our research group (3). Particular interest has been focused on green bioactive total extracts or molecules by food waste matrices. The analyzed matrices were the following: seeds of Vitis vinifera cvs Michele Palieri and Italia; rosemary leaves, olive patè, pigmented potatoes, pomegranate fruits and vineatrol. In the preparation of final formulations, among excipients in commercially available, have been used inulin and maltodextrin (4). The total antioxidant capability has been evaluated as in vitro scavenging activity against ABTS●+ monocationic radical. All samples were analyzed and compared for their ROS-scavenging properties before and after the treatment with ionizing radiations (140 cSv, calculated as the amount of radiations absorbed by astronauts after an hypothetical stay of three years in the space). Matrices selected for highest antioxidant properties will be also analyzed in ex vivo biological essays using blood red cell membranes in order to test the in vivo protective effects on a biological system. The chemical profiles of the matrices selected were evaluated, before and after the treatment, by HPLC-DAD and HPLC-MS-TOF analyses. In vitro results obtained showed that the treatment with a high dose of radiation does not induced significant modifications in the total antioxidant capability and phenolic composition of the extracts. This study has been supported by Agenzia Spaziale Italiana (ASI) PAPARD project contract number 2014-34-RO. These results could have relevant impacts for space mission, but they also could have interesting output in biomedicine. The intake of food supplements or pharmaceutical formulations rich in antioxidant bioactive molecules could help to protect patients against damages caused by medical therapies, like as imaging and diagnostics technologies and radiotherapy, that involve exposure to ionic radiations. Fig. 1. Antioxidant activity of different plant extracts radiated (140 cSv) and not radiated. 1) F.A. Cucinotta, M. Durante (2006). The lancet oncology, 7:431-435 2) V.M. Mikhailenko, E.A. Diomina, I.I. Muzalov, & B.I. Gerashchenko, (2013). Experimental oncology, 35(1), 58-64 3) A.R. Santamaria, N. Mulinacci, A. Valletta, M. Innocenti, G. Pasqua (2011). J. Agric.Food Chem.. 59:9094- 9101 4) V. Pasqualetti, A. Altomare, M. Guarino, V. Locato, S. Cocca, S. Cimini, R. Palma, R. Alloni, L. De Gara, M. Cicala (2014). Plos One 9 (5); e98031, 2014